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atomic_light11
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AM amplitude modulation---
Hi everyone, I am learning AM recently, but I have some question that keep troubling me..
1. We know that AM wave is produced by the multiplication of carrier wave and modulation wave. But why does the equation of AM wave is not a direct multiplication of Vm×Vc but consist of a constant? Can anyone explain the general concept of the AM wave equation?
Why it is
Vam = [Ec + Emcos(ωmt)]cos(ωct)
but not
Vam = [Eccos(ωct)] [Emcos(ωmt)]
2. In single sideband AM, why does the cancelling of one sideband doesn't affect the information in the wave? And what is the effect to the wave pattern after the AM wave has been transform from double sideband (DSBFC) to single sideband (SSBFC)?
Thanks!
Hi everyone, I am learning AM recently, but I have some question that keep troubling me..
1. We know that AM wave is produced by the multiplication of carrier wave and modulation wave. But why does the equation of AM wave is not a direct multiplication of Vm×Vc but consist of a constant? Can anyone explain the general concept of the AM wave equation?
Why it is
Vam = [Ec + Emcos(ωmt)]cos(ωct)
but not
Vam = [Eccos(ωct)] [Emcos(ωmt)]
2. In single sideband AM, why does the cancelling of one sideband doesn't affect the information in the wave? And what is the effect to the wave pattern after the AM wave has been transform from double sideband (DSBFC) to single sideband (SSBFC)?
Thanks!
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